Apparatus for automatic gas lift operation of oil wells



Oct. 19, 1965 D. cRYER APPARATUS FOR AUTOMATIC GAS LIFT OPERATION 0F oILWELLS Filed Sept. 2, 1959 2 Sheets-Sheet 1 IN V EN TOR.`

DEL CRYER BY.' lo

WSL

ATTORNEY Oct. 19, 1965 D. CRYER 3,212,579

APPARATUS FOR AUTOMATIC GAS LIFT OPERATION OF OIL WELLS Filed Sept. 2,1959 2 Sheets-Sheet 2 Tim'. 5

INVENTOR.'

DEL CRYER ATTORNEY United States Patent 3,212,579 APPARATUS FORAUTOMATIC GAS LIFT OPERATIN 0F OIL WELLS Bel Cryer, Giddeus-.Jane Bldg.,Shreveport, La. Filed Sept. 2, 1959, Ser. No. 837,630 4 Claims. (Cl.166-52) This invention relates to an apparatus for automatic gas liftoperation of oil wells.

Gas lift operation of oil wells in the past has been wasteful ofequipment and gas when operated individually, and unsatisfactory inperformance and also wasteful of gas when operated in groups.

Therefore i-t is an object of my invention to provide apparatus for thegas lift operation of oil wells, either singly or in groups, which iseconomical to manufacture and gives improved performance.

Other and further objects and advantages of my invention will beapparent from the following specication taken in conjunction with theaccompanying drawings, wherein corresponding characters of referencedesignate the same or similar parts throughout the several views, and inwhich:

FIG. 1 is a diagrammatic layout view of the apparatus employed in mysystem.

FIG. 2 is a schematic wiring diagram of the apparatus shown in FIG. l.

FIG. 3 is a side elevation of the automatic high pressure multipleoutlet valve employed in my system.

FIG. 4 is a top plan view of the valve shown in FIG. 3.

FIG. 5 is a fragmentary vertical cross sectional view of the valve shownin FIG. 3, with parts broken away.

FIG. 6 is a fragmentary plan view of lthe valve shown in FIG. 3, withparts broken away.

FIG. 7 is a horizontal cross sectional View taken along the line 7 7 inFIG. 5, on an enlarged scale.

Referring more in detail to the drawings, an important feature of myinvention is the automatic high pressure multiple outlet valve 10, thedetails of which will be describer hereinafter. Sullice it to say atthis point that the valve is provided with a plurality of outlets t0 beconnected, respectively, to the several wells to be operated as a group,here shown as four in number and designated as 11, 11a, 11b and 11C. Asis customary in the art, each of the wells is provided with a casing 12,a two inch tubing 13 inside the casing, and a one inch tubing 14 insidethe two inch tubing. An outlet of the valve is connected to supply gasunder pressure to the two inch tubing in each of the wells by means ofthe pipe lines 15, 15a, 15b and 15C, respectively.

Another feature of my invention is that the one inch tubing at the topof each well is provided with an upward extension 16 beyond the coupling17 at which the pipe line 1S takes off the gas and oil coming up fromthe well through the one inch tubing 14. Similar extensions 16a, 1Gb and16C, couplings 17a, 17b and 17C, and pipe lines 18a, 18h and 18C areprovided for the wells 11a, 11b and 11e, respectively. The extension 16,which is of course axially aligned with the one inch tubing, isconnected at its upper portion to one end of a small one-quarter inchtubing 9 which is connected at its other end to the pipe line 18.Similar connections are provided as shown at 19a, 19b and 19C on theother wells.

The purpose of the extension 16 on the upper end of the one inch tubingand the by-pass connection 19 is to provide a shock absorber for therabbit customarily employed in gas lift operation of oil wells, and thefunctioning of this device will be explained hereinafter.

The pipe lines 18, 18a, 18]) and 18C may be connected directly to a gasand liquid separator, or they may be connected into a header 20 andthence through a commou pipe line 21 to the gas and liquid separator 223,212,579 Patented Get. 19, 1965 ICC which will be recognized by thoseskilled in the art as a separator of prior art construction.

Liquid from the gas and liquid separator 22 is conducted by pipe line 23to the oil and water separator 24, of conventional construction, fromwhich waste water is taken by means of the conduit 25, and oil passes bymeans of the conduit 26 to the oil storage tank 27.

Gas from the gas and liquid separator 22 passes by means of pipe line 28through the scrubber tank 29 and thence by pipe line 30 to the inletside of the motor driven compressor 31 which supplies gas under pressurethrough the pipe line 32 in response to actuation of the pressureresponsive switch which is set to maintain pressure in the tank 33between 500 p.s.i. maximum and 290 p.s.i. minimum, for example. Shut-olfvalve 35 is manually operated to be closed if it is desired to makerepairs or changes in the valve 10. The multiple outlet valve 10 isautomatically operated in response to electric timer 36 to supplyoperating gas under pressure through the pipe lines 15, 15a, 15b, 15C,selectively, to the wells being operated.

Another feature of my invention is that excess gas from the gas andliquid separator 22 which is not needed immediately for return to thegas storage tank 33, instead of being released as was previously done,is conducted by pipe line 38 into the casing of at least one of thewells for temporary storage under pressure, the pressure beingcontrolled at about 15 p.s.i. by mean of pressure relief valve 39 in thepipe line 38.

Referring more particularly to FIGS. 3 through 7 in the drawings, itwill be seen that my automatic high pressure multiple outlet valvecomprises a cylindrical body 40 provided with a plurality of outletports 41, 41a, 41b and 41o communicating respectively with pipe lines15, 15a, 15b and 15e. The valve body 4t) is closed at the bottom bybottom plate 42 and is closed at the top by top plate 43. The bottomplate 42 is supported upon a base plate 44 which is supported abovefloor plate 45 by a plurality of legs 45.

Interiorly, the valve body 4) is provided with a rotor 47 which :isjournaled for rotation at 48 and 49 in the top :and bottom plates,respectively. The rotor 47 has an outer periphery conforming closely tothe inner periphery of the valve body 40 except in one small portion ofits periphery, here shown as about the rotor is cut away along iasubstantially straight line to form la cavity Sli between the rotor andthe inner periphery of the valve body. Extending radially inward fromthe cut away portion of the periphery, the valve body is provided with aradial bore 51 which extends past the center of the rotor. Through thehub journaled at 49 is the bottom plate 42, the valve body is providedwith an axial bore 52 which at its inner end is in `communication withthe radial bore 51 and at its outer end is in communication with pipeline 37 through swivel connections 37. A Teflon plug or bushing 5Shaving an enlarged head 56, making it somewhat mushroom shaped, isprovided with a through bore 57 axially thereof and is carried in theradial bore 51 in the rotor 47 with the outwardly extending ange of .theunderside of the enlarged head abutting the flattened cut away portionof the periphery of rotor 47. O ring S3 around the shank of the plug 55prevents leakage from the radial bore 51 into the cavity 50 whilepermitting slight sliding movement of the plug 55 in the radial bore 51.The outer face of the Teflon plug or bushing 55 rests snugly against theinner periphery of the cylindrical valve body 40. In order to press theTeflon bushing 55 firmly ragainst the inner wall of the valve body, theinner end of the Tellen bushing which is received within the bore 51 isabutted by a collar 58 which is pressed thereagainst by coil spring 59,the collar 58 being slidably positioned within the bore 51. The otherend of the coil spring 59 is engaged over a floating plug 60 which isslidably mounted in a radial bore 51. The rotor is tapped and threadedto receive an adjusting screw 62 which loosely engages the floating plug60 for in and out movement thereof to adjust the tension on spring 59pressing the collar 58 and plug 55 outwardly against the inner peripheryof the valve body 40. A screw driver or other tool may be insertedthrough one of the outlet ports in valve body for adjustment of thescrew 62, this end of the radial bore 63 being closed by a pipe plug 64after the adjustment has been made and until the next adjustment isnecessary.

Extending upwardly from the rotor 47 through the journal at 48 is therotor drive shaft 65 which is connected by gears 66, 67 through speedreducer 63 to the valve motor 69, the valve motor and speed reducerbeing mounted upon an upper plate 70 supported by a plurality of legs 71mounted on the base plate 44. The gear 66 is provided on its upper facewith an index plate 72 which carries a plurality of index lugs 73, onefor each outlet in the valve body, and one for each space betweenoutlets, eight such lugs being here shown (FIG. 6) spaced 45 apartcorresponding to the spacing of the four outlets and four intermediatespaces in the embodiment of the valve yas shown. The index lugs arearranged to engage the actuating finger 74 of the micro-switch 75.

In the operation of the foregoing system according to my invention,assuming that the rotor 47 in the multiple outlet valve 10 is alignedwith the Teflon bushing 55 overlying the outlet port 41, gasunderpressure will pass from storage tank 33 through line 37 to theaxial inlet bore 52 in the valve 10 and thence through the radial bore51 and Teiion bushing 55 to the outlet port 41 with which the pipe lineis connected to supply the gas under pressure to the two inch tubing inthe well 11. The gas under pressure then passes down through the twoinch tubing 13, opens the customary bottom hole gas lift valve (notshown), and enters the lower end of one inch tubing 14 to force thecustomary rabbit therein upwardly and carrying with it the accumulatediluid (gas and oil) which is taken off through the pipe line 18 at thecoupling 17 until the rabbit passes the coupling 17. Thereafter, withoutthe provision of my extension 16 on the one inch tubing, there would bea great hammering of the rabbit against the upper end of the tubing, butaccording to my invention the tubing 16 permits the rabbit to climb pastthe coupling 17 and the small amount of liquid remaining above therabbit is forced out through the small one-quarter inch diameter tubing19 which forms Ia by-pass back around the pipe line 18, this smallby-pass tubing permitting the remaining liquid carried above the rabbitto escape slowly and thereby provide a cushioning effect for the rabbitwhich after coming to a stop, -again descends to the bottom of the wellthrough the one inch tubing to pick up another accumulation of fluid.This operation continues for the programmed time set on the timer 36 forlifting fluid from the well, and as gas continues to be supplied throughthe pipe line 15 the rabbit continues to operate up and down in the oneinch tubing carrying above it each time a slug of iiuid to be deliveredthrough the pipe line 18 into the gas yand liquid separator 22, the oiland water passing therefrom through the pipe line 23 into the oil andwater separator 24 from whence the oil passes through the conduit 26into the oil storage tank 27. Meanwhile, back at the gas and liquidseparator 22, the gas passes out through the pipe line 2S, through thescrubber 29 where any condensate is taken out, and thence through thepipe line 30 to the inlet side of the motor driven compressor 31 whichsupplies compressed gas through the pipe line 32 to replenish the supplyin the storage tank 33 so as to maintain the pressure thereinapproximately between 500 p.s.i. maximum and 290 p.s.i minimum.Connected in parallel with the inlet side of the motor driven compressor31 is the pipe line 38 which has its other end connected into the casingon well 11, for example, so that any gas coming through the pipe line 28and not immediately needed or required by the inlet side of motor drivencompressor 31 is temporarily stored in the casing 12 of wall 11, thusproviding a closed, recycling system for the utilization and storage ofthe gas coming from the oil iield as an incident to the lifting of oilfrom the wells therein. Each of the other wells, in which gas is notbeing stored, is provided with a gas let-off pipe line 181:1, 181b,181C, respectively, interconnecting the associated well casing with itsassociated pipe line to the gas and liquid separator 22, each suchlet-olf pipe line being provided with a check valve, as shown, to permitgas under pressure to flow from the well casing to the separator 22, butnot reversely. It will be noted in FIG. 2 that the motor drivencompressor 31 is connected across the electric supply line to supply gasunder pressure to the storage tank 33 any time required in response tothe actuation of the pressure controlled switch 34 mounted on the tank33. It will Ialso be noted that upon the elapse of the programmed timefor the lifting of oil from well 11, the associated switch in the timer36, which according to the prior art may have a plurality of camoperated switches, one for each of the lugs 73 on the multiple outletvalve 10, will be closed; and upon the closing of any one of theparallel connected switches in the timer 36 switch 101 will be closedwhereby a circuit is established through the contacts of normallyclosed, thermal delay switoh 102 and through the valve motor 69, thuspermitting valve motor 69 to start running, even though the micro switchon the valve is at that instant held open by an index lug 73 on thevalve, but upon running of the motor 69 to index the valve 10,microswitch 75 will promptly close to complete a circuit in parallelwith the contacts of switoh 102 which at that time is still closedbecause of the thermal delay; however, after a predetermined period oftime the thermal time delay relay coil of switch 102 will open thecontacts of that switch, but the relay coil of that switch 102 willcontinue to be excited until the timer 36 progresses suiciently to closethe parallel connected switch therein which it had just opened.Meantime, the valve motor 69 continues to run and index the multipleoutlet valve 10 until micro-switch 75 is opened upon contact of itsactuating finger 74 with the next index lug 73 which will open themicro-switch 75 and break the circuit to the valve motor 69. At thistime the rotor 47 in the multiple outlet valve 10 is aligned with theTeflon bushing 55 midway between the outlet port 41 and the outlet port41a, assuming that the direction of rotation is clockwise, although itcould be counterclockwise. In this position the bore through the Teflonbushing 55 is sealed off tightly against the inner periphery of thevalve body 40, being urged thereagainst by the spring 59 and by thepressure of the operating gas against the end of the bushing 55 in theradial bore 51, so that the flow of operating gas under pressure iscompletely shut off by the multiple outlet valve.

When the programmed time elapses for the waiting period before liftingoil from the next Well, the timer 36 will close the parallel connectedswitch therein associated with that phase of the operation so as toagain close switch 101 to complete a circuit through the contacts ofnormally closed thermal delay switch 102 and through the valve motor 69,thus permitting valve motor 69 to start running again and the indexingof the valve 10 proceeds as before until the micro-switch 75 is openedupon contact of its actuating finger 74 with the next index lug 73 whichwill open the micro-switch 75 and break the circuit to the valve motor69 when the rotor 47 in the multiple outlet valve 10 is aligned with theTeflon bushing 55 overlying the outlet port 41a, Ias shown in FIG. 7,thereby resetting the mechanism to supply gas under pressure for thepredetermined programmed length of time as determined by the setting ofthe cams in the timer 36, which after the programmed time will close theparallel connected micro-switch therein associated with that phase ofthe operation to again initiate operation of the valve motor 69, asbefore, to index it to a position such that the Teilon bushing 55 isagain sealed off against the inner Wall of the valve body 40, this timemidway between outlet ports 41a and 41b. This cycle of operationcontinues throughout the 360 rotation of the multiple outlet valve, thevalve body being provided with as many outlet ports as are necessary toaccommodate the number of wells on the lease, it being understood thattwo index lugs 73 are provided for each such outlet port, one to alignthe rotor with the outlet port and the other to align the rotor with thewall median between adjacent ports, and it will also -be understoodtha-t any or as many of the outlet ports may be closed off as desired,and any scheduled stops may be eliminated by merely removing thecorresponding lug, or lugs, 73, and of course the programming of theentire cycle of operations, and all phases thereof, are fully andindependently adjustable for suitable programming to meet the demandsand desires of the operator.

Having thus described my method and apparatus for automatic gas liftoperation of oil Wells, it will be apparent to those skilled in the artthat the method and apparatus which I have provided is highly efficient,entirely automatic, and economical in the use of gas in this closedsystem which provides for the recycling yof the operating gas and thetemporary storage of excess gas in one of the wells on the lease, butthat many modications and changes may be made without departing from thespirit or scope of my invention as defined by the app-ended claims.

I claim:

1. Apparatus for automatic gas lift operation of a plurality of oilwells having an outer casing, intermediate tubing within said casing andinner tubing within said intermediate tubing, comprising a multipleoutlet valve with an outlet connected respectively to the intermediatetubing in each of said Wells for supplying operating gas under pressurethereto selectively, a gas and liquid separator connected to receive gasand liquid from the inner tubing in each of said wells, an oil and waterseparator connected to receive liquid from said gas and liquid separatorand adapted to separate oil from water and separately discharge thesame, an operating gas storage tank operatively connected to supply gasunder pressure to said valve, pump means operably connected to supplyand maintain gas under pressure in said storage tank withinpredetermined limits, pipe means interconnecting said pump means withthe gas outlet of said gas and liquid separator for supplying gas tosaid pump means, and a pipe line interconnecting the casing in one ofsaid wells with the gas outlet of said gas and liquid separator forconducting excess gas from said gas and liquid separator to said one ofsaid wells for temporary storage of excess gas therein.

2. Apparatus according to claim 1 wherein said valve is indexed inselectively supplying gas to said wells and including motive power meansand timer means operiatively connected to said valve for indexing saidvalve to supply operating gas under pressure to said wells according toa predetermined program.

3. Apparatus -according to claim 2 including a bleed-oit valveoperatively connected to the pipe line interconnecting the casing ofsaid one of said wells with the gas outlet of said gas and liquidseparator.

4. Apparatus for automatic gas lift operation of la plurality of oilwells having an outer casing, intermediate tubing within said casing`and inner tubing wit-hin said intermediate tubing, comprising amultiple outlet valve with an outlet connected respectively to theintermediate tubing in each of said Wells for supplying operating gasunder pressure thereto selectively, said valve being indexed inselectively supplying gas to said Wells, a gas and liquid separatorconnected to receive gas and liquid from the inner tubing in each ofsaid wells, an oil and Water separator connected to receive liquid fromsaid gas and liquid separator and adapted to separate oil from Water andseparately discharge the same, an operating gas storage tank operativelyconnected to supply gas under pressure to said valve, pump meansoperatively connected to supply and maintain gas under pressure in saidstorage tank within predetermined limits, pipe means interconnectingsaid pump means with the gas outlet of said gas and liquid separator forsupplying gas to said pump means, motive power means and timer meansoperatively connected to said valve for indexing said valve to supplyoperating gas under pressure to said Wells according to a predeterminedprogram, a pipe line interconnecting the casing of said one of saidwells with the gas outlet of said gas and liquid separator and ableed-oit valve operatively connected to said pipe line.

References Cited by the Examiner UNITED STATES PATENTS 971,612 10/10Holliday 103-52 1,520,737 12/24 Wright 166-6 1,798,774 3/31 Yates166--75 X 1,812,267 6/31 Lewis 166--6 2,034,798 3/36 Clark 166-22,309,075 1/43 Hill 166-7 2,570,553 10/51 Hawley 166-6 2,623,596 12/52Whorton et al. 166-7 2,624,410 1/53 Nixon 166-75 2,741,265 4/56 Poor137-625.11 2,773,551 12/56 Warden et al. 166-75 2,806,486 9/57 McDonaldetal. 137-625.11 X 2,821,998 2/58 Mayhew 137-625.11 2,994,372 8/61 Stone166-7 OTHER REFERENCES Uren, Lester C.: Petroleum ProductionEngineering, Oil Field Exploitation, 2nd edition, New York, McGraw-Hill, 1939.

CHARLES E. OCONNELL, Primary Examiner. BENJAMIN BENDETT, Examiner.

1. APPARATUS FOR AUTOMATIC GAS LIFT OPERATION OF A PLURALITY OF OILWELLS HAVING AN OUTER CASING, INTERMEDIATE TUBING WITHIN SAID CASING ANDINNER TUBING WITHIN SAID INTERMEDIATE TUBING, COMPRISING A MULTIPLEOUTLET VALVE WITH AN OUTLET CONNECTED RESPECTIVELY TO THE INTERMEDIATETUBING IN EACH OF SAID WELLS FOR SUPPLYING OPERATING GAS UNDER PRESSURETHERETO SELECTIVELY, A GAS AND LIQUID SEPARATOR CONNECTED TO RECEIVE GASAND LIQUID FROM THE INNER TUBING IN EACH OF SAID WELLS, AN OIL AND WATERSEPARATOR CONNECTED TO RECEIVE LIQUID FROM SAID GAS AND LIQUID SEPARATORAND ADAPTED TO SEPARATE OIL FROM WATER AND SEPARATELY DISCHARGE THESAME, AN OPERATING GAS STORAGE TANK OPERATIVELY CONNECTED TO SUPPLY GASUNDER PRESSURE TO SAID VALVE, PUMP MEANS OPERABLY CONNECTED TO SUPPLYAND MAINTAIN GAS UNDER PRESSURE IN SAID STORAGE TANK WITHINPREDETERMINED LIMITS, PIPE MEANS INTERCONNECTING SAID PUMP MEANS WITHTHE GAS TO SAID PUMP MEANS LIQUID SEPARATOR FOR SUPPLYING GAS TO SAIDPUMP MEANS, AND A PIPE LINE INTERCONNECTING THE CASING IN ONE OF SAIDWELLS WITH THE GAS OUTLET OF SAID GAS AND LIQUID SEPARATOR FORCONDUCTING EXCESS GAS FROM SAID GAS AND LIQUID SEPARATOR TO SAID ONE OFSAID WELLS FOR TEMPORARY STORAGE OF EXCESS GAS THEREIN.